Speed limiter removal - changing clocks?

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SonicSW20
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Joined: Mon Nov 29, 2010 7:54 pm

Speed limiter removal - changing clocks?

Post by SonicSW20 »

Converted my revision 5 UK car to a gen3 turbo. Being a UK car, it of course has MPH clocks already.

I have seen a few references to people saying that changing the clocks to 160MPH UK clocks on a turbo also disables (or possibly raises?) the speed limiter. The speed limiter is very much still in place in my car.

Is this complete b0ll0cks, or are there some other differences with Japan market turbos that would mean changing clocks would affect the limiter on those but not a UK car?
markstevieandmads
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Re: Speed limiter removal - changing clocks?

Post by markstevieandmads »

I was Getting issues with power steering not going off when it should and was told it was the convertor thingy (cheap resistor type thing) so i disconnected it and installed uk clocks which has helped.
However ive not reinstalled the convertor thingy but noticed i havent got a speed limiter yet i can do 130mph easy?!?! My clocks are accurate to 80mph as checked with gps so wouldnt have thought it will go much out the faster i go.
My car is orginal jdm turbo.

So going back to your point, ive never confirmed the uk clocks / speed limiter conversion.
SonicSW20
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Re: Speed limiter removal - changing clocks?

Post by SonicSW20 »

markstevieandmads wrote:I was Getting issues with power steering not going off when it should and was told it was the convertor thingy (cheap resistor type thing) so i disconnected it and installed uk clocks which has helped.


Yeah, that makes sense - those converters alter the speed signal, which the power steering ECU uses to determine how much assistance to provide, so you'll be getting 30mph assistance level at 50mph!

markstevieandmads wrote:
However ive not reinstalled the convertor thingy but noticed i havent got a speed limiter yet i can do 130mph easy?!?! My clocks are accurate to 80mph as checked with gps so wouldnt have thought it will go much out the faster i go.
My car is orginal jdm turbo.

That's odd. Mine cuts at somewhere between 110 and 120 on the clocks. Another way to delimit is to simply cut the SPD signal to the ECU, but this would normally throw a code and EML will be on.

markstevieandmads wrote:
So going back to your point, ive never confirmed the uk clocks / speed limiter conversion.


I've been using all my Google-fu, but can't find anything that would confirm it. You'd think that with my car already having these alleged magic clocks it would already be delimited :-k

I have an HKS SLD to go on at some point anyway, I'm just curious at this point!
pbmr2
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Re: Speed limiter removal - changing clocks?

Post by pbmr2 »

was the converted ecu loom hooked up correctly to the chassis loom so the ecu gets the speed reading from the NA clocks?
Race Idiot
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Location: Hertfordshire

Re: Speed limiter removal - changing clocks?

Post by Race Idiot »

My rev3 import turbo is definitely limited to around 120mph, I can get the needle to hit the bottom on the back straight at bedford as it's still got the 180kmh clocks with different faces.

I should really fit the stef derner de-limiter I've had lying around for ages. But then I wonder how that will play with a standalone ecu.
SonicSW20
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Joined: Mon Nov 29, 2010 7:54 pm

Re: Speed limiter removal - changing clocks?

Post by SonicSW20 »

pbmr2 wrote:was the converted ecu loom hooked up correctly to the chassis loom so the ecu gets the speed reading from the NA clocks?


I simply repinned the 22p (body loom) plug at the ECU, as that's the easiest way to do it. Engine side wiring is untouched, only thing I did have to do is run a new wire for the circuit opening relay.

Race Idiot wrote:My rev3 import turbo is definitely limited to around 120mph, I can get the needle to hit the bottom on the back straight at bedford as it's still got the 180kmh clocks with different faces.

I should really fit the stef derner de-limiter I've had lying around for ages. But then I wonder how that will play with a standalone ecu.


You won't need the delimiter with a standalone ECU!
Race Idiot
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Location: Hertfordshire

Re: Speed limiter removal - changing clocks?

Post by Race Idiot »

So the steering should work correctly then? I guess the power steering gets the speed from the clocks?
SonicSW20
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Re: Speed limiter removal - changing clocks?

Post by SonicSW20 »

Race Idiot wrote:So the steering should work correctly then? I guess the power steering gets the speed from the clocks?


Not entirely sure of the routing... Don't see why not though.
shinny
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Location: Reading, UK

Re: Speed limiter removal - changing clocks?

Post by shinny »

Gazza_DJ wrote:I have seen a few references to people saying that changing the clocks to 160MPH UK clocks on a turbo also disables (or possibly raises?) the speed limiter. The speed limiter is very much still in place in my car.

Is this complete b0ll0cks?


It's complete BS. The type of dials have no affect on the speed signal received by the ECU. The dials only come into it all when starting to think about converting faces AND delimiting on the same car.

If you're keeping the 160mph dials then just do the delimiting at the ECU; this could most easily be done via an mph/kph converter wired in at the ECUraising the limit beyond the gearing of the car. That avoids touching dials or PAS.
SonicSW20
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Joined: Mon Nov 29, 2010 7:54 pm

Re: Speed limiter removal - changing clocks?

Post by SonicSW20 »

It didn't sound right, thanks for confirming Shinny.

I have an HKS SLD that I was planning on wiring in at the ECU.
shinny
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Joined: Mon Nov 27, 2006 4:59 pm
Location: Reading, UK

Re: Speed limiter removal - changing clocks?

Post by shinny »

Gazza_DJ wrote:It didn't sound right, thanks for confirming Shinny.

I have an HKS SLD that I was planning on wiring in at the ECU.


Bingo... job done :thumleft:
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